To run a beta version, you need a product key. Feel free to have a look at the features comparison to know which edition is the best for you if you are interested in buying Tacview.

Please note that even if we are doing our best to produce a high quality product, beta versions usually contains known and unknown bugs, may crash, or have some features disabled because of work in progress. This is why, it is suggested to download and install beta versions alongside the latest official release (not over it). That way, in case of problem, you can simple launch the latest stable version to continue your work...